World Health Organization (WHO) Director-General Tedros Adhanom Ghebreyesus has suggested that racism is behind a lack of international attention being paid to the plight of civilians in Ethiopia's war-shattered Tigray region, slamming global leaders for overlooking the humanitarian crisis.

Calling it the "worst humanitarian crisis in the world," with 6 million people unable to access basic services, Tedros, who is himself from Tigray, suggested racism may be why the situation ranked behind Ukraine in terms of international attention, despite it being "the worst humanitarian crisis."

"Maybe the reason is the color of the skin of the people," Tedros, who is from Tigray, told a virtual media briefing on Wednesday. In April this year at a briefing, he questioned whether "black and white lives" in emergencies worldwide are given equal attention.

In November 2020, Ethiopian Prime Minister Abiy Ahmed ordered troops into the region to topple the Tigray People's Liberation Front, accusing rebels of attacking federal army camps.

Since the war broke out, Ethiopia's northernmost region has suffered food shortages and access to basic services such as electricity, communications and banking has been severely limited.

"As a result, the people of Tigray are facing multiple outbreaks of malaria, anthrax, cholera, diarrhea and more," Tedros told a WHO press conference in Geneva.

"This unimaginable cruelty must end. The only solution is peace."

Fighting has eased in northern Ethiopia since a humanitarian truce was declared at the end of March, allowing the resumption of desperately needed international aid convoys to Tigray.

In recent weeks both sides have mooted the possibility of peace talks.

But Tedros said only a trickle of food and medicines had made it into the region and said basic services must be resumed in order to build confidence in the peace negotiations.

WHO emergencies director Mike Ryan also hit out at an apparent shortage of concern about the drought and famine unfolding in the Horn of Africa, and the ensuing health crisis.

"No one seems to give a damn about what's happening in the Horn of Africa," said Ryan, speaking at a virtual media briefing on Wednesday.

The WHO called for $123.7 million to tackle the health problems resulting from growing malnutrition in the region, where around 200 million people live and millions are going hungry.